Pontoon boats, using pairs of pontoon logs as flotation devices for supporting the deck of a pontoon boat, are a popular recreational water item. The deck of a pontoon boat is typically large enough to accommodate several people simultaneously during travel of the pontoon boat across a body of water.
Traditionally, pontoon logs used to support a pontoon boat deck were a generally hollow enclosure, with the air entrapped in the hollow enclosure providing the requisite buoyancy to maintain the boat afloat. The hollow enclosure is typically formed of a thin sheet of metal. To provide increased structural integrity to the thin sheet of metal forming the hollow enclosure, billets of polystyrene foam have been inserted into the hollow enclosure in a T-shaped configuration, extending the length of the pontoon log.
While the billets of polystyrene foam are buoyant and therefore provide some degree of flotation in the event of a puncture of the metal forming the hollow enclosure of the pontoon logs, the polystyrene billets do not prevent water from flooding the log interior through the puncture opening. The flooding of the interior of the pontoon log displaces the air therein and thereby significantly reduces the buoyancy of the pontoon log.
Accordingly, there is a need for a pontoon log having a structural support for its interior which prevents the influx of water into the pontoon log in the event it is punctured. This is desired to assure that the pontoon boat remains steadily afloat in the event of a puncture to one of its pontoon logs.
U.S. Pat. No. 4,777,898 discloses a pontoon log in which the entire interior of the pontoon log is completely filled in with flotation foam. While this construction provides the desired protection against influx of water into the pontoon log interior in the event of a puncture, this construction suffers several shortcomings. Principally, the quantity of flotation foam required to completely fill the pontoon log interior adds considerable expense to the pontoon logs. Additionally, the large volume of foam required to completely fill the pontoon log interior adds considerable undesirable weight.
There is a need for a pontoon log having the ability to withstand a puncture to its shell without resulting in flooding of the pontoon log interior which is less expensive and lighter in weight than pontoon logs having their entire interior filled with flotation foam.
Still further, there is a need for such a pontoon log which also lends itself to welding of a top cover to seal the top of a pontoon log without affecting the watertight integrity of the pontoon log.